This invention relates to an apparatus for the installation of a flexible lateral seal which is impregnated with a curable resin, and more particularly to an apparatus having a silicone bladder with a cavity for receiving the flexible lateral seal and which can be inflated to form a seal along the main pipeline and invert the lateral seal into the lateral pipeline from the main is pipeline.
The most widely practiced method of lining existing pipelines and conduits using a flexible resin impregnated lining or xe2x80x9ccured in place pipexe2x80x9d is the Insituform(copyright) Process and is described in U.S. Pat. Nos. 4,009,063 and 4,064,211, the contents of which are incorporated herein by reference. Briefly, in the Insituform(copyright) Process, an elongated flexible tubular lining of a resin impregnable material, such as a needled felt, which has been impregnated with a thermosetting synthetic resin, is installed within an existing pipeline that is in need of repair. The impregnated liner may be pulled into the conduit by a rope or cable, and a fluid-impermeable inflation bladder or tube is then everted within the liner as described in detail in U.S. Pat. No. 4,009,063. Alternately, the liner is installed utilizing an eversion process as described in U.S. Pat. No. 4,064,211. The liners utilized in the Insituform(copyright) Process are flexible and generally have a smooth impermeable coating on one side. After inversion, this smooth layer becomes the inside of the liner.
After the flexible liner is positioned within the conduit, the liner is pressurized from within, preferably using a fluid such as water. The fluid pressure forces the liner radially outwardly to engage and conform to the interior surface of the existing pipeline. The resin is then cured by recirculating heated water to form a relatively hard, tight-fitting rigid pipe lining that effectively relines the existing pipeline. In addition to curing by heat, the resin can be cured using other forms of radiant energy, such as ultra violet light as described in U.S. Pat. No. 4,135,958 or visible light in U.S. Pat. No. 4,518,247 and No. 4,680,066, the contents of which are incorporated herein by reference. Alternatively, radiant energy in the form of electrical energy or sound waves can be used to initiate the cure. Once the liner is completely cured, lateral connections are cut to existing services to the liner by remote cutters, which are common expedients in the art.
There is a strong demand and a need to seal the connections between the main conduit and any lateral pipes, in addition to the repair of the main pipeline. This is an important consideration in the process of relining an entire existing sewer system in order to effectively prevent the ingress of ground water into the system and outflow of effluent from the system.
In a typical municipal sewer system, there are a plurality of lateral pipeline entering a main conduit between adjacent manhole access points. The time needed to cure a cured in place liner that has been installed in a main pipeline is typically between four and six hours. Using existing methods of lining or lateral pipelines or is not possible to perform any significant repair or lining operations of the plurality of lateral connections at the same time that a main conduit is being lined. Repair or sealing of each lateral connection using conventional lining methods is difficult. Such long cure times would generally increase the amount of time required to complete the repair of a particular line by almost a full day of work for each lateral connection. Since a typical residential street may have about ten or more homes between manholes, this would increase the operating time needed to complete the lining operation for repair of the main pipeline between adjacent manholes from one day to ten days or more.
There are presently several proposals available for lining lateral pipelines and forming a seal at the lateral connection.
Some of these call for lining the lateral from the outlet of the service lateral inward to the mainline conduit. One such method is described in U.S. Pat. No. 5,108,533. Others utilize a launcher-type apparatus that inserts a lining from the main pipeline into the lateral connection at a location remote from the access to the main pipeline. This process is described in U.S. Pat. No. 5,624,629, the contents of which are incorporated herein by reference. Here, a second or subsequent lateral is lined and cured, at the same time as an initial lateral is being lined in an effort to reduce the overall time of repair of the system. However, because several laterals are typically connected to a particular mainline conduit, it is difficult and almost physically impossible to install lateral seals at more than one location within a mainline conduit at the same time.
Accordingly, it is desirable to provide a device suitable for installation of a flexible lateral seal at the intersection between a lateral pipeline and a main pipeline which can be efficiently operated from a remote location for providing installation from the mainline into the lateral. It is desirable to improve the speed and cycle time required to install a lateral seal in order to provide truly cost effective repair of lateral intersections.
Generally speaking, in accordance with the invention, an apparatus for installing a cured in place lateral seal having a brim portion bonded to a short tubular section is provided. The apparatus includes a cartridge assembly having a cylindrical flexible bladder with an extendible arm which can be tucked into the bladder to form a recess for receiving the tubular portion of the seal with the brim seated on the outer portion of the bladder. The cartridge assembly is removably mounted on a sled or robot device with positioning motors for positioning the seal at the exact location of the lateral. Use of a replaceable cartridge allows the operator to load a new seal wetted with curable resin on a cartridge as another seal on the sled is being cured in place for rapid exchange.
The bladder is secured to the ends of a cylindrical hollow frame to form a cartridge assembly which has an inlet for introduction of pressurized fluid for inflating the bladder to press the brim portion of the seal against the interior of the main pipeline and everting the arm and tubular portion of the seal out of the recess into of the lateral to form the lateral seal. The cure can be initiated by introduction of heated fluid or electrical power for powering radiant energy source within the bladder such as light energy, either UV or visible, sound or microwaves.
The sled includes on at least one end a lift motor to place the brim portion of the lateral seal on the surface of the main pipeline at the lateral opening. It may include separately operable lift motors at both end of the cartridge. The sled may also include at least one rotational motor for rotating the cartridge circumferentially to align the brim of the seal with the lateral opening.
Accordingly, it is an object of the invention to provide an improved device for installing a flexible cured in place lateral seal into the junction between a main pipeline and lateral connection from inside the main pipeline.
Another object of the invention is to provide an improved device for installing a flexible cured in place lateral seal, including a cartridge holding the resin impregnated lateral seal which can be replaceably mounted on a delivery sled for assembly.
A further object of the invention is to provide an improved bladder cartridge for insertion into a delivery sled for the rapid installation of flexible cured in place lateral seals from the mainline of an existing conduit.
Still another object of the invention is to provide an apparatus for the installation of a curable resin lateral seal providing a source of radiant energy with a bladder assembly.
Yet another object of the invention is to provide a bladder apparatus for the installation of a light curable resin lateral seal providing a source of curing light within the bladder apparatus.
Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.
The invention accordingly comprises the several steps and the relation of one or more of such steps with respect to each of the others, the apparatus embodying features of construction, combination(s) and arrangement of parts which are adapted to effect such steps, and the product which possesses the characteristics, properties, and relation of constituents (components), all as exemplified in the detailed disclosure hereinafter set forth, and the scope of the invention will be indicated in the claims.